[X11] Match win32 wheel coordinate system
authorthefiddler <stapostol@gmail.com>
Tue, 10 Jun 2014 12:53:23 +0000 (14:53 +0200)
committerthefiddler <stapostol@gmail.com>
Tue, 10 Jun 2014 12:53:23 +0000 (14:53 +0200)
commit525af589f1c9ac38415a0ead1b9f2bb029688aed
treec703764f080e0dc5123de8f2d381bc051bea36dc
parentb9e948580a5e7b6ff5f72a7a44783768221fbf45
[X11] Match win32 wheel coordinate system

OpenTK uses the win32 wheel coordinate system, where
(+h, +v) = (right, up). XI2 uses (+h, +v) = (right, down)
instead, so we need to flip the vertical offset.

Fixes issue #133 and https://github.com/mono/MonoGame/issues/2686
Source/OpenTK/Platform/X11/XI2MouseKeyboard.cs